Open2 sheds some light: in response to Pete’s musings, I immediately thought that the beans/UK craze might be a first world war thing – tinned rations at the front, shared experience of hardship, a generation shaped ect ect.

But no – though introduced to the UK at around the turn of the 19th century, Heinz didn’t start making beans here until the 20s (and for most of the bean’s history in Britain, Heinz enjoyed a virtual monopoly).

The turning point seems to have been World War II, when GIs gave the baked bean some exotic elan, and then I suspect a big surge in the 1950s for two reasons:

– affluent society and changing lifestyles leading to more demand for convenience food.
– increased popularity of cafes – this is where the bean will have come into its own as a snack and as part of the breakfast.

In the broader history of the GBB I’d posit a shift away from the GBB in the early 20th century containing kippers and so on – an aspirational meal served up at home, ideally by a Jeeves-ish figure – and towards the GBB as we know it now, a comfort meal with the emphasis firmly on “what comes well out of a frying pan”. The bean may be the axis on which this change pivots.